HATCHER : OLIGOCENE CANID^ 91 



well up on the antero-internal surface of the tuberosit}', as in recent dogs and cats. 

 The lesser process or sustentaculum is much more expanded than in either the dogs 

 or cats. It bears the internal articular surface for the astragalus. This surface is 

 elliptical in outline. Superiorly it is separated from the external articular surface 

 by a shallow groove for the interosseous ligament, and inferiorly by a rather wide 

 rugose area. The greater process is much broader and shorter than in recent dogs 

 and cats and shows no articular surfaces for the neck and head of the astragalus. 

 The peroneal tubercle is more prominent than in recent cats and the groove for the 

 peroneus longus tendon is deeper. The articular surface for the cuboid is subcircular, 

 regularly concave and looks almost directly downward as in the dogs instead of 

 downward and inward as in the cats. There is a large, rugose tuberosity on the 

 posterior side of the distal end. Owing to the abbreviated nature of the distal por- 

 tion the calcaneum does not come in contact with the navicular. 



The astragalus is feline throughout. The head is much expanded transversely 

 and the neck is even more constricted than in most modern cats. The neck and 

 head are inclined sharply inward from the axis of the trochlea and the head pre- 

 sents an elongated, elliptical articular surface for the navicular, which is convex in 

 all directions. The trochlea is not so convex supero-inferiorly as in the recent 

 canidse or felidse, but in other respects it does not differ materially from that surface 

 in the cats. The tibial side is low and narrow, the fibular high and wide, and they 

 are separated by a wide gingiymoid groove which may be a little shallower than 

 in the modern cats, but is decidedly deeper than in Hoplophoneus. On the plantar 

 side the external and internal articular surfaces for the calcaneum are separated by 

 a deep, narrow groove for the interosseous ligament. These articular surfaces do not 

 differ from the corresponding ones in the astragalus of the cat. 



Owing to the abbreviated greater process of the calcaneum and the unreduced 

 neck and head of the astragalus the inferior surface of the latter falls below the in- 

 ferior portion of the calcaneum and comes in contact laterally with the cuboid, a 

 condition which, in so far as I know, does not obtain in either the dogs or cats of 

 the present day, but is to be observed, though to a less extent, in Hoplophoneus. 

 By reason of the abbreviated nature of the inferior portion of the calcaneum, which 

 thus allows the cuboid to articulate laterally with the ectocuneiform, the navicular 

 and the head of the astragalus, the cuboid is proportionately elongated in Daphoenus. 

 Its superior surface for articulation with the calcaneum is regularly but gently con- 

 vex. Inferiorly it articulates with metacarpals IV. and V. by a single, slightly con- 

 cave articular surface. On the internal side there are two articular surfaces for 

 contact with the ectocuneiform, separated by a broad, shallow groove. One of these 



